Injection valve for an internal combustion engine

ABSTRACT

An injection valve for an internal combustion engine, especially an injection valve for an internal combustion engine with an electronically controlled gasoline injection system in which the injection valve is secured at the internal combustion engine under interposition of a heat-insulating bush, which preferably has no contact whatsoever with the injection valve.

United States Patent 1191 Schiifer 1 51 Oct. 15,- 1974 [541 INJECTION VALVE FOR AN INTERNAL 3,131,866 5/1964 Cummins et a1. 123/32 R COMBUSTION ENGINE 3,334,617 8/1967 Palkowsky 123/32 R 3,605,703 9/1971 Moulds 123/32 EA Inventor: Manfred Schlifer, Am Sonnenhang 3,628,510 1 2/1971 Moulds 123/32 EA 25, 7056 Beutelsbach, Germany 3,695,235 10/1972 Anderson 123/32 R [22] Filed: Oct. 1972 Primary Examiner-Laurence M. Goodridge [21] Appl. No.: 295,693 Assistant Examiner-Cort Flint Attorney, Agent, or Firm-Craig & Antonelli [30] Foreign Application Priority Data Oct. 6, 1971 Germany 2149817 [57] ABSTRACT An injection valve for an internal combustion engine, [52] U.S. Cl 123/32 R, 123/32 JV especially an injection valve for an internal combus- [51] Int. Cl. F02m 61/14 i gin with an l ctroni ally controlled gasoline [58] Field of Search 123/32; 239/533 inj i n sy em in which he injection valve is secured at the internal combustion engine under interposition [56] References Cited of a heat-insulating bush, which preferably has no UNITED STATES PATENTS contact whatsoever with the injection valve.

2,846,986 8/1958 Parsons 123/32 R 9 Claims, 1 Drawing Figure INJECTION VALVE FOR AN INTERNAL- COMBUSTION ENGINE The present invention relates to an injection valve for an internal combustion engine, especially to an injection valve for an internal combustion engine with electronically controlled gasoline fuel injection.

In internal combustion engines with electronically controlled gasoline fuel injection, 21 poor starting behavior and an irregular idling can be observed after a high loading of the internal combustion engine and/or after high outside temperatures because the injection valves are heated up and the fuel is evaporated within the injection valves in the metering gap between the nozzle needle and the nozzle neck.

The present invention is concerned with the take to avoid a heating up of injection valves and therewith to prevent an evaporation of the fuel.

The underlying problems are solved according to the present invention in that the injection valve is secured at the internal combustion engine under interposition of a head-insulating bush or sleeve.

One succeeds by means of the present invention to prevent with few expenditures an evaporation of the fuel. As a result thereof, the starting behavior becomes normal and the idling becomes even and quiet.

In one advantageous embodiment of the subject matter of the present invention, the head-insulating sleeve may exhibit only a small contact area with the part of the internal combustion engine at which it is secured.

With an injection valve which is secured under interposition of a rubber ring serving the purposes of sealing, the heat-insulating bush or sleeve can be advantageously so constructed that is has no contact whatsoever with the injection valve itself.

Furthermore, the bush or sleeve can consist in a simple manner of a polyamide of any conventional type possibly reinforced with glass fibers.

Accordingly, it is an object of the present invention to provide an injection valve for an internal combustion engine which avoids by simple means the aforementioned shortcomings and drawbacks encountered in the prior art.

Another object of the present invention resides in an injection valve for an internal combustion engine, particularly for an internal combustion engine with electronic fuel injection, which greatly improves the starting behavior and idling of the engine even after long high engine loads and/or high outside temperatures.

Still a further object of the present invention resides in an injection valve for internal combustion engines which avoids an evaporation of the fuel within the injection valve.

Another object of the present invention resides in an injection valve for internal combustion engines, particularly with gasoline injection, which avoids by simple means entailing few expenditures all of the aforementioned shortcomings and effectively achieves all of the aforementioend aims.

These and further objects, features, and advantages of the present invention will become more apparent from the following description when taken in connection with the accompanying drawing which shows, for purposes of illustration only, one embodiment in accordance with the present invention, and wherein:

The single FIG. is a partial cross-sectional view through an injection nozzle for an internal combustion engine wit gasoline fuel injection in accordance with the present invention.

Referring now -to the single FIG. of the drawing, reference numeral 1 designates therein the cylinder head of an internal combustion engine which is equipped with an electronically controlled gasoline injection system of known type. An injection valve 3 of any conventional construction is arranged in the cylinder head 1 under interposition of a rubber ring 2. In order to prevent that heat is transmitted from the cylinder head 1 primarily by conduction onto the valve neck 4 of the injection valve 3, the injection valve 3 is secured at the cylinder head 1 by interposition of cup-shaped sleeve or bush 5. The sleeve 5 consists of a heat-insulating material, of any suitable known type, for example, of a conventional polyamide possibly reinforced with glass fibers, and it has only a small area as contact area with the cup-shaped cylinder head I. The sleeve or bush 5 has no contact whatsoever with the injection valve 3.

It is avoided by means of the cup-shaped sleeve or bush 5 that the temperature threshold at which an evaporation of the fuel takes place on the inside of the injection valve 3, is exceeded. This temperature threshold lies at approximately 90 to 100 Celsius.

While I have shown and described only one embodiment in accordance with the present invention, it is understood that the same is not limited thereto but is susceptible of numerous changes and modifications as known to those skilled in the art, and I therefore do not wish to be limited to the details shown and described herein but intend to cover all such changes and modifications as are encompassed by the scope of the appended claims.

What I claim is:

1. An injection valve arrangement for an internal combustion engine, comprising: an injection valve secured at the internal combustion engine, a heatinsulating sleeve means interposed between said injection valve and the engine, said heat-insulating sleeve means being provided with only a small area contacting that part of the internal combustion engine at which it is secured, an elastic ring means interposed between said injection valve and said heat insulating sleeve means, said heat-insulating sleeve means having no contact whatsoever with the injection valve.

2. An injection valve arrangement according to claim 1, characterized in that the internal combustion engine includes an electronically controlled gasoline fuel injection system.

3. An injection valve arrangement according to claim 1, wherein said sleeve means consists of a polyamide.

4. An injection valve arrangement according to claim 1, wherein said sleeve means consist of a polyamide reinforced with glass fibers.

5. An injection valve arrangement according to claim 4, wherein the internal combustion engine includes an electronically controlled gasoline fuel injection system.

6. An injection valve arrangement for an internal combustion engine, comprising: an injection valve secured at the internal combustion engine, a heatinsulating sleeve means interposed between said injection valve and the engine, an elastic ring means interposed between said injection valve and said head insulating sleeve means, said heat-insulating sleeve means having no contact whatsoever with said injection valve.

7. An injection valve arrangement according to claim 6, wherein said sleeve means consists of a polyamide.

8. An injection valve arrangement according to claim 6, wherein said sleeve means consists of a polyamide reinforced with glass fibers.

9. An injection valve arrangement for an internal combustion engine having a cylinder head, the arrangebase portion. 

1. An injection valve arrangement for an internal combustion engine, comprising: an injection valve secured at the internal combustion engine, a heat-insulating sleeve means interposed between said injection valve and the engine, said heat-insulating sleeve means being provided with only a small area contacting that part of the internal combustion engine at which it is secured, an elastic ring means interposed between said injection valve and said heat insulating sleeve means, said heat-insulating sleeve means having no contact whatsoever with the injection valve.
 2. An injection valve arrangement according to claim 1, characterized in that the internal combustion engine includes an electronically controlled gasoline fuel injection system.
 3. An injection valve arrangement according to claim 1, wherein said sleeve means consists of a polyamide.
 4. An injection valve arrangement according to claim 1, wherein said sleeve means consist of a polyamide reinforced with glass fibers.
 5. An injection valve arrangement according to claim 4, wherein the internal combustion engine includes an electronically controlled gasoline fuel injection system.
 6. An injection valve arrangement for an internal combustion engine, comprising: an injection valve secured at the internal combustion engine, a heat-insulating sleeve means interposed between said injection valve and the engine, an elastic ring means interposed between said injection valve and said head insulating sleeve means, said heat-insulating sleeve means having no contact whatsoever with said injection valve.
 7. An injection valve arrangement according to claim 6, wherein said sleeve means consists of a polyamide.
 8. An injection valve arrangement according to claim 6, wherein said sleeve means consists of a polyamide reinforced with glass fibers.
 9. An injection valve arrangement for an internal combustion engine having a cylinder head, the arrangement comprising: an injection valve secured at the cylinder head, a Substantially cup-shaped heat insulating member interposed between said injection valve and the cylinder head, said substantially cup-shaped member including an annular base portion and a peripheral wall extending between and spaced from said injection valve and the cylinder head, said annular base portion having at least a small portion thereof directly contacting the cylinder head and an elastic ring means interposed between said injection valve and said annular base portion. 